Method for generating a negative group delay and associated electronic device and computer program product

Abstract

A method for generating, by an electrical device based on an input signal, an output signal that exhibits a negative group delay. The method includes the following steps, carried out by a programmable digital processing unit of the device: obtaining a sampling frequency associated with a digital signal representative of the input signal; obtaining a target negative group delay value; determining a set of coefficients for a differential equation according to the sampling frequency and the target negative group delay value; calculating, upon acquiring a current value of the digital signal, a corresponding current value of the output signal by using the differential equation.

1 . A method comprising:
 generating, by an electronic device, from a signal supplied as input to said electronic device, an output signal having a negative group delay with respect to said input signal, the generating comprising at least one iteration of the following acts, implemented by a programmable digital processing unit of said electronic device:   obtaining a sampling frequency associated with a digital signal representative of said input signal;   obtaining a group delay value, referred to as a target negative group delay value, said target negative group delay value being controlled by said programmable digital processing unit to be less than or equal to a quarter of a current rise or fall variation time of said input signal when said input signal is non-deterministic, or to a quarter of a period of said input signal when said input signal is periodic;   determining a set of coefficients from a difference equation, as a function of said sampling frequency and said target negative group delay value, said difference equation defining a relationship between a value of said output signal, a value of said input signal and at least one previous value of said input signal and/or said output signal; and   calculating, on acquisition of a current value of said digital signal, a corresponding current value of said output signal, by using said difference equation.   
     
     
         2 . The method according to  claim 1 , wherein said difference equation is determined as a function of an operating mode selected from a recursive mode and a non-recursive mode, and as a function of an order associated with said operating mode. 
     
     
         3 . The method according to  claim 1 , wherein said input signal is an analogue signal, and the method comprises an analogue-to-digital conversion of said input signal, said conversion comprising sampling said input signal at said sampling frequency, providing said digital signal representative of said input signal. 
     
     
         4 . The method according to  claim 3 , comprising, prior to said analogue-to-digital conversion, conditioning said analogue input signal. 
     
     
         5 . The method according to  claim 1 , wherein said sampling frequency of the input analogue signal is controlled by said programmable digital processing unit. 
     
     
         6 . The method according to  claim 5 , wherein said sampling frequency of the input analogue signal is adapted as a function of a current rise and/or fall time of said input signal. 
     
     
         7 . An electronic device for generating an output signal having a negative group delay with respect to an input signal supplied as input to said electronic device, said electronic device being comprising:
 an input for receiving the input signal;   an output for supplying the output signal; and   a programmable digital processing unit configured to:   obtain a sampling frequency associated with a digital signal representative of said input signal;   obtain a group propagation time value, referred to as target negative group propagation time value, said target negative group propagation time value being controlled by said programmable digital processing unit so as to be less than or equal to a quarter of a time of current variation in rise or fall of said input signal when said input signal is non-deterministic, or to a quarter of a period of said input signal when said input signal is periodic;   determine a set of coefficients of a difference equation as a function of said sampling frequency and said target negative group propagation time value, said difference equation defining a relationship between a value of said output signal, a value of said input signal and at least one previous value of said input signal and/or said output signal;   calculate, on acquisition of a current value of said digital signal, a corresponding current value of said output signal, by using said difference equation.   
     
     
         8 . The electronic device according to  claim 7 , comprising an analogue-to-digital converter which samples said input signal at said sampling frequency, delivering said digital signal representative of said input signal, when said input signal is analogue. 
     
     
         9 . The electronic device according to  claim 7 , wherein said programmable digital processing unit belongs to the group consisting of:
 a microcontroller;   a virtual machine running on a computer;   A Field Programmable Gate Array (FPGA)-type programmable prediffused integrated circuit;   and an Application Specific Integrated Circuit (ASIC)-type integrated circuit with a specific application.   
     
     
         10 . A non-transitory computer readable medium comprising program code instructions stored thereon for executing a method, when executed on a computer of an electronic device, wherein the method comprises:
 generating, by the electronic device, from a signal supplied as input to said electronic device, an output signal having a negative group delay with respect to said input signal, the generating comprising at least one iteration of:   obtaining a sampling frequency associated with a digital signal representative of said input signal;   obtaining a group delay value, referred to as a target negative group delay value, said target negative group delay value being controlled by said programmable digital processing unit to be less than or equal to a quarter of a current rise or fall variation time of said input signal when said input signal is non-deterministic, or to a quarter of a period of said input signal when said input signal is periodic;   determining a set of coefficients from a difference equation, as a function of said sampling frequency and said target negative group delay value, said difference equation defining a relationship between a value of said output signal, a value of said input signal and at least one previous value of said input signal and/or said output signal; and   calculating, on acquisition of a current value of said digital signal, a corresponding current value of said output signal, by using said difference equation.